So people have had similar problems showing colors on .ply files here and here but I don't think this is the same case. I've exported a .ply file from a program called paraview with color info on it. I've uploaded the file here and as you can see, the color info came with it.
But for whatever reason when I import it into blender and go look for the per-vertex color info where I would expect to find it, its empty:
Am I doing something wrong? It seems like there had been a problem with importing .ply color for a bit in 2.80, but this is 2.81. I would assume it was fixed?